Systems and methods for battery impedance matching to facilitate improved battery charging

ABSTRACT

Systems, methods, and apparatus for providing a homopolar generator charger with an integral rechargeable battery. A method is provided for converting rotational kinetic energy to electrical energy for charging one or more battery cells. The method can include rotating, by a shaft, a rotor in a magnetic flux field to generate current, wherein the rotor comprises an electrically conductive portion having an inner diameter conductive connection surface and an outer diameter conductive connection surface, and wherein a voltage potential is induced between the inner and outer diameter connection surfaces upon rotation in the magnetic flux field. The method can also include selectively coupling the generated current from the rotating rotor to terminals of the one or more battery cells.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/851,295, filed Apr. 17, 2020, which is a continuation of U.S.application Ser. No. 15/377,235, filed Dec. 13, 2016, now U.S. Pat. No.10,673,257, which is a continuation of U.S. application Ser. No.13/869,642 filed Apr. 24, 2013, now U.S. Pat. No. 9,553,463, whichclaims priority to U.S. Provisional Application Ser. No. 61/637,810filed Apr. 24, 2012 and is a continuation-in-part of U.S. applicationSer. No. 13/435,312 filed on Mar. 20, 2012, now U.S. Pat. No. 8,581,559,which is a continuation of U.S. Pat. No. 8,164,228 issued on Apr. 24,2012 and filed on Oct. 12, 2011, the entire contents of which areincorporated by reference herewith.

TECHNICAL FIELD

This invention generally relates to battery charging, and in particular,to a homopolar electrical generator charger for a rechargeable battery.

BACKGROUND

A homopolar generator is a unique electrical generator, sometimesreferred to as a Faraday disk after Michael Faraday, who developed thebasic device in 1831. The homopolar generator can convert rotationalenergy into direct current by rotating an electrically conductive discin a plane perpendicular to a magnetic field. Faraday's law ofelectromagnetic induction and/or Lorentz's force law can be utilized toexplain the operation of the homopolar generator. The radial movement ofthe electrons in the disc in the presence of the magnetic field producesa charge separation between the center of the disc and its rim, and ifthe circuit is completed between the disk center and rim, an electriccurrent will be produced when the disc is rotated.

Versions of the homopolar generator have been used to supply currents upto 2 million amperes, but practical use has been limited due primarilyto the low voltage output and high I²R losses that can arise fromimperfect electrical brush connections to connect external circuits.

Conventional battery chargers and alternators are typically designed forcharging several battery cells in series, with charging currents limitedby the additive internal resistance of each cell in the series. Chargingcells of a battery in series tends to require extended charging periods.For example, a typical multi-cell 10 ampere-hour battery requiresroughly 15 hours to reach full charge from a fully discharged conditionwith a 1 ampere charger.

Electric cars and other electric vehicles utilize battery packs havingmultiple rechargeable cells that are connected in series to provideadequate voltages for driving electric motors. One of the barriers forcommercial success of the all electric car, however, is the longassociated battery charging times. Part of the issue that can contributeto the long charging time is the internal series resistance that limitsthe amount of charging current that can flow through the battery. Somedesigners and manufactures have proposed systems to swap out the entirebattery each time it is discharged to address the charging time issue.

BRIEF SUMMARY

Some or all of the above needs may be addressed by certain embodimentsof the invention. Certain embodiments of the invention may includesystems, methods, and apparatus for a homopolar generator with integralrechargeable battery.

According to an example embodiment of the invention, an apparatus isprovided. The apparatus includes an elongated shaft defining alongitudinal axis of rotation; at least one rechargeable batterycomprising at least one cell having a positive and negative terminal,the at least one battery mounted substantially coaxially with respect tothe shaft; one or more magnets for providing a magnetic flux field; arotor comprising an electrically conductive portion having an innerdiameter conductive connection surface and an outer diameter conductiveconnection surface, the rotor mounted coaxially in communication withthe shaft, wherein the rotor is operable to rotate in the magnetic fluxfield; at least one positive output electrode operable for selectiveelectrical communication with at least one of the battery cell positiveterminal, the rotor inner diameter conductive connection surface, or therotor outer diameter conductive connection surface, wherein the at leastone positive output electrode is stationary relative to the rotatingshaft; at least one negative output electrode operable for selectiveelectrical communication with at least one of the battery cell negativeterminal, the rotor outer diameter conductive connection surface, or therotor outer diameter conductive connection surface, wherein the at leastone negative output electrode is stationary relative to the rotatingshaft; and a connection system comprising one or more brushes forelectrically connecting one or more of the rotor conductive connectionsurfaces or the battery terminals with one or more of the outputelectrodes. According to an example embodiment, the rechargeable batteryis operable to rotate with the rotor.

According to another example embodiment, a system is provided. Thesystem includes a motor; an elongated shaft defining a longitudinal axisof rotation; at least one rechargeable battery comprising at least onecell having a positive and negative terminal, the at least one batterymounted substantially coaxially with respect to the shaft; one or moremagnets for providing a magnetic flux field; a rotor comprising anelectrically conductive portion having an inner diameter conductiveconnection surface and an outer diameter conductive connection surface,the rotor mounted coaxially in communication with the shaft, wherein therotor is operable to rotate in the magnetic flux field; at least onepositive output electrode operable for selective electricalcommunication with at least one of the battery cell positive terminal,the rotor inner diameter conductive connection surface, or the rotorouter diameter conductive connection surface, wherein the at least onepositive output electrode is stationary relative to the rotating shaft;at least one negative output electrode operable for selective electricalcommunication with at least one of the battery cell negative terminal,the rotor outer diameter conductive connection surface, or the rotorouter diameter conductive connection surface, wherein the at least onenegative output electrode is stationary relative to the rotating shaft;and a connection system comprising one or more brushes for electricallyconnecting one or more of the rotor conductive connection surfaces orthe battery terminals with one or more of the output electrodes.

According to another example embodiment, a method is provided forconverting rotational kinetic energy to electrical energy for chargingone or more battery cells. The method includes rotating, by a shaft, arotor in a magnetic flux field to generate current, wherein the rotorincludes an electrically conductive portion having an inner diameterconductive connection surface and an outer diameter conductiveconnection surface, and wherein a voltage potential is induced betweenthe inner and outer diameter connection surfaces upon rotation in themagnetic flux field; and selectively coupling the generated current fromthe rotating rotor to terminals of the one or more battery cells,wherein the terminals comprise a positive terminal and a negativeterminal, and wherein the positive terminal and a negative terminal areelectrically connected to respective inner and outer, or outer and innerdiameter connection surfaces, wherein the at least one battery cell ismounted substantially coaxially with respect to the shaft.

Other embodiments, features, and aspects of the invention are describedin detail herein and are considered a part of the claimed inventions.Other embodiments, features, and aspects can be understood withreference to the following detailed description, accompanying drawings,and claims.

BRIEF DESCRIPTION OF THE FIGURES

Reference will now be made to the accompanying tables and drawings,which are not necessarily drawn to scale, and wherein:

FIG. 1 is a diagram of an illustrative homopolar generator rotor,according to an example embodiment of the disclosure.

FIG. 2 is a side-view depiction of an illustrative homopolar generatorcharger with an integral battery, according to an example embodiment ofthe disclosure.

FIG. 3 is a side-view depiction of another illustrative homopolargenerator charger with an integral battery, according to an exampleembodiment of the disclosure.

FIG. 4 is a diagram a rechargeable battery for use with the homopolargenerator charger, according to an example embodiment of the disclosure.

FIG. 5 is a circuit diagram of a homopolar generator charger with arechargeable battery and a stationary switching controller, according toan example embodiment of the disclosure.

FIG. 6 is a circuit diagram of a homopolar generator charger with arotating rechargeable battery and switching controller, according to anexample embodiment of the disclosure.

FIG. 7 is a flow diagram of an example method according to an exampleembodiment of the disclosure.

FIG. 8 depicts an example configuration of an apparatus for matchingimpedances between source and load, according to an example embodimentof the disclosure.

FIG. 9 illustrates an example computer simulation of an exampleconfiguration of the disclosure.

FIG. 10 illustrates an example configuration of a homopolar generator,according to an example embodiment of the disclosure.

FIG. 11 illustrates an example track housing that includes variouscomponents of the homopolar generator, according to an embodiment of thedisclosure.

FIG. 12 illustrates an example configuration of the homopolar generatorthat includes multiple magnet arrays, according to an embodiment of thedisclosure.

FIG. 13 illustrates an example configuration of a shaft with respect toa rotor of the homopolar generator, according to an embodiment of thedisclosure.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the invention will be described more fully hereinafterwith reference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Example embodiments can include a homopolar generator having one or morerechargeable battery cells. In example embodiments, electricalconnections may be selectively switched to connect the cells to thehomopolar rotor center and rim during rotation to charge and/ordischarge the cells simultaneously. In an example embodiment, the one ormore rechargeable battery cells can be selectively switched, whenappropriate, to an external circuit for providing DC current output.According to example embodiments, the one or more cells can beselectively connected in parallel during charging or discharging. In anexample embodiment, two or more cells can be connected in series toprovide increased DC voltages for output to an external circuit.According to example embodiments, the rechargeable battery cells mayrotate with the conductive rotor and a switching controller to eliminateone or more pairs of brush connections and/or to provide low resistanceswitchable connections from the generator rotor to the battery cells.

The present application hereby incorporates by reference in its entiretyU.S. Pat. No. 7,592,094 to Shawn Kelley, et. al., entitled “Device,System, and Method for Improving Efficiency and Preventing Degradationof Energy Storage Devices.”

Various parts may be used and arranged for achieving efficient batterycharging, according to example embodiments of the invention, and willnow be described with reference to the accompanying figures.

FIG. 1 depicts an illustrative homopolar generator 100 with a rotor 102,according to an example embodiment. According to an example embodiment,the rotor 102 includes at least a conductive surface. In other exampleembodiments, the rotor 102 may be a solid conductive disk. In accordancewith example embodiments, additional rotors may be utilized in thehomopolar generator charger. In example embodiments, the conductiveportion of the rotor may include metals with high conductivity,preferably copper. However, other metals including silver, gold,aluminum, nickel, etc may be utilized.

According to an example embodiment, the rotor 102 may be in mechanicaland electrical contact with a shaft 104, which may provide linkage forrotation, and may provide a rotor inner diameter connection surface. Inexample embodiments, the rotor may include an outer diameter connectionsurface 108. In accordance with example embodiments, a voltage potentialmay be induced between the inner diameter (in electrical connection withthe shaft 104, for example) and the outer diameter connection surface108. The voltage polarity is dependent on the direction of rotation andthe orientation of the magnetic field with respect to the rotorrotation. The voltage magnitude is a function of the square of the rotorradius, the rotation speed, and the magnetic field strength. Accordingto an example embodiment, the rotor radius 110 may be set to provide acertain voltage output for a rotation speed and magnetic field strength.According to other example embodiments, the shaft 104 may beelectrically isolated from the rotor 102, and an inner diameterconnection surface may be provided for completing a circuit for whichcurrent may flow.

FIG. 2 is a side-view depiction of an illustrative homopolar generatorwith an integral battery 200, according to an example embodiment. Inthis example embodiment, a magnet assembly, having a north pole 201 anda south pole 202, may provide a magnetic flux 206 for interaction withthe conductive rotor 212. In an example embodiment, the 201, 202 may bejoined by an optional return path 208 to assist in aiding return flux210 and to reduce the magnetic reluctance associated with the magneticflux path. According to example embodiments, the magnets, as describedherein, may have a sufficient diameter to produce a magnetic field witha diameter that is larger than the diameter of the rotor so that theentire rotor is exposed to the magnetic field. According to exampleembodiments, multiple permanent magnets may be arranged, for example, inan adjacent north-south-north-south configuration, or with interveningcomponents between the magnets.

According to one example embodiment, the magnet assembly may bemechanically separated from the shaft 204 and mounted separately so thatthe shaft 204 and other attached components may rotate independentlyfrom the magnet assembly. In another example embodiment, the magnetassembly may be mechanically coupled with the shaft 204, and the magnetassembly may rotate with the shaft 204. Certain advantages/disadvantagesin terms of weight, inertia, mounting complexity, etc. for example, mayprovide reasoning for rotating the magnets, or for providing stationarymagnets. A surprising result that is not readily apparent from Faraday'slaws is that it does not matter whether the magnetic field rotates ornot. In one embodiment, rotating magnets may add to the mass of thegenerator and may require more inertial energy to spin the rotor whilenot otherwise changing the outcome in any useful way. However, accordingto another example embodiment, it may be advantageous to have the extramass of the spinning magnet for storage of rotational energy.

According to example embodiments, the homopolar generator 200 includes arechargeable battery 216. In one example embodiment, the rechargeablebattery 216 can be fixed to the shaft 204 and/or the conductive rotor212, and may rotate with these parts. In another example embodiment, theshaft 204 and/or the conductive rotor 212 can be configured to rotateindependent of the rechargeable battery 216.

According to example embodiments, the shaft 218 may provide an innerdiameter connection surface for providing a slideable electricalconnection with a first electrode brush 218. In an example embodiment,the conductive rotor 212 can include an outer diameter connectionsurface (as in 110 of FIG. 1) for providing a slideable electricalconnection with a second electrode brush 220. In accordance with exampleembodiments, if the rechargeable battery 216 may include two or moreouter diameter connection surfaces for slideable electrical connectionswith battery electrode brushes 222. According to example embodiments,two brushes may be utilized to provide circuit connection access to thepositive and negative terminal of the rechargeable battery. In exampleembodiments, multiple rechargeable battery cells 216 may be utilized inthe homopolar generator charger 200, each with similar connections forexternal circuits, as previously described.

According to example embodiments, and as will be further explained withreference to FIGS. 3, 5, and 6, a switching controller may be used toselectively connect, switch, and/or disconnect circuits associated withthe homopolar generator charger 200.

Many other configurations for the rechargeable batteries 216, theconductive rotor 212, the magnets 201, 202, and the associatedconnecting components may be envisioned without departing from the scopeof the inventions. For example, it may be advantageous to electricallyisolate the shaft 204 from the rest of the mechanism. In such an exampleembodiment, an optional insulator 214 may be utilized to electricallyseparate the inner diameter of the conductive rotor 212 from the shaft204. In this example embodiment, the first electrode brushes 218 may beconfigured to contact with an inner diameter of the conductive rotor212, at a slideable connection surface on the conductive rotor at adiameter outside the region of the optional insulator 214.

FIG. 3 depicts yet another example embodiment of a homopolar generator300 having a battery 308 and a switching controller 320 that areoperable for rotating with the conductive rotor 306. In this exampleembodiment, the magnet 301 may be configured to be stationary, or it maybe configured to rotate with the shaft 304, the conductive rotor 306,the switching controller 310 and the battery 308. In this exampleembodiment, one magnet 301 is depicted having opposing poles 302 in aplane perpendicular to the conductive rotor 306 so that the magneticlines of flux pass substantially perpendicularly through the conductiverotor. Other example embodiments may include more than one magnet 301(such as in FIG. 1).

The following illustrative example may help provide part of thereasoning for having a direct electrical connection configuration, asshown in FIG. 3. A mid-sized, typical homopolar generator may bedesigned to produce an output of 3 volts at a current of 1000 amperes (3KW). A slip ring pair with brushes for connecting with the rotor mayhave a combined series resistance of 0.01 ohm. The I²R loss associatedwith brush connections is 1000²×0.01=10 KW, which is three times greaterthan the output of the generator. Therefore, the typical homopolargenerator almost always ends up being extremely inefficient. Accordingto example embodiments, FIG. 3 depicts direct electrical connections320, 322 from the conducting rotor to the switching controller 310, anddirect electrical connections 316, 318 to/from the battery 308.According to example embodiment, direct electrical connection mayprovide low resistance connections among the rotor 306, controller 320,and battery 308 so that I²R losses may be minimized.

In the example embodiment of FIG. 3, first electrode brushes 312 andsecond electrode brushes 314 may be utilized for electrically completingconnections from the switching controller 310 to external circuits. Forexample, the first electrode brush 312 may connect to a ground ornegative portion of an external (and non-rotating) circuit, and secondelectrode brush 314 may connect to a positive portion of the externalcircuit, or vice versa.

According to example embodiments of the invention, the directconnections 316, 318, 320, 322 may provide low resistance connectionsfor charging the battery 308. In certain example embodiments, thebattery 308 may include multiple cells, each with direct connection tothe controller 310. According to an example embodiment, the controller310 may provide connections for hooking each of the battery cells inseries for outputting power at higher voltages, and perhaps lowercurrents, so that less power is lost at the electrode brushes 312, 314,which provide slideable electrical connections, for example, tonon-rotating external circuits. Additional details for this embodimentwill be further described in reference to FIG. 6.

FIG. 4 depicts an example rechargeable battery 400, having an anode 402a cathode 404, a first electrode 406, and a second electrode 408.According to an example embodiment, the rechargeable battery 400 mayinclude a separator 410 between the anode 402 and the cathode 404.According to an example embodiment, the anode and cathode placement maybe switched to provide opposite polarity for the battery outputelectrodes. According to example embodiments, the polarity of thebattery, which may depend on the orientation or placement of the anodeand cathode, may be matched with the polarity output from the homopolargenerator rotor, which depends on the direction of rotation of therotor, and the orientation of the magnetic field. According to oneexample embodiment, the rechargeable battery 400 may rotate with theshaft, the rotor, and switching controller. In such an embodiment, thebattery electrodes 406, 408 may be directly connected to connectionsassociated with a switching controller (as in FIG. 3). In anotherexample embodiment, the battery may be configured to be non-rotating, orto rotate independently from the rotor. In such embodiments, an optionalbearing 412 may be utilized so that the shaft may rotate independent ofthe battery 400.

FIG. 5 depicts an example circuit diagram of a homopolar generatorcharger 500 with a non-rotating switching controller 506. In thisexample embodiment, a motor 530 may be utilized to turn the rotor 502.(The magnetic field is not shown in this diagram, but it is assumedpresent with the correct orientation). According to an exampleembodiment, a battery 504 (or optionally, two or more cells as indicatedby the dashed lines) may be selectively connected to the rotor 502 or tooutput connections 516, 518, 520, 522 via battery brushes 512, 514,and/or the rotor outer brush 510 and shaft brush 508. In an exampleembodiment, the switching controller 506 may connect the rotor positiveportion to an output 524, which may be configured for outputindependent, or in conjunction with the battery output. According toexample embodiments, the switching controller may be utilized forconnecting two or more battery cells 504 in parallel for charging, andmay be operable to isolated cell positive and negative outputs forserial connection of the batteries for higher voltage output. Inaccordance with example embodiments, the switching controller 506 mayelectrically disconnect one or more connections with the rotor 502 whenthe rotor speed falls below a given threshold value, or when chargingcurrent associated with the batteries has reached a predetermined value.

FIG. 6 depicts an example circuit diagram of a homopolar generatorcharger 600 with an integrated switching controller 605 and battery orcells 604 that are operable to rotate with the rotor 602. The examplecircuit diagram of FIG. 6 may correspond to a configuration similar tothat as shown in FIG. 3. According to an example embodiment, a motor 620may be used to rotate the rotor 602, the switching controller 605, andthe battery or cells 604. In other example embodiments, the rotor 602,switching controller 605, and the battery or cells 604 may be rotatedvia components associated with a regenerative braking system. Accordingto an example embodiment, the rotor 602, switching controller 605, andthe battery or cells 604 rotate in concert and at least some of theelectrical connections between these devices may be hard wired.According to an example embodiment, two output brushes 610 may providean electrical connection from the components that are operable forrotating, to a non-rotating positive output electrode 612 and anon-rotating negative electrode 614. According to example embodiments,the reduction of brushes may provide power efficiency advantages, aspreviously discussed. In accordance with certain example embodiments,the output brushes 610 may be placed in close proximity to (or on) therotor shaft of the homopolar generator charger 600 to reduce frictionand to minimize wear.

According to example embodiments, the switching controller 605 mayinclude one or more switching networks 607 that may be utilized toselective close and open circuits among the rotor 602, the battery orcells 604, and the output brushes 610. In example embodiments, one ormore diodes may be utilized to limit current flow to one direction inany of the circuits. According to example embodiments, relays or otherswitching devices having high current capacity and low resistance whenengaged may be utilized for switching elements in the switching network607. In example embodiments, the controller 605 may additionally includea microprocessor 606, a rotation sensor 608, a voltage detector 618,and/or a battery 609. In another example embodiment, a receiver and/ortransmitter may be included in the controller 605 for wirelesscommunication with an external controller.

According to an example embodiment, the microprocessor 606 may beutilized for receiving information, and for directing the switchingnetwork 607 based upon input such as rotation speed, rotation direction,etc. According to example embodiments, the voltage detector circuit 618may be used for monitoring the voltage across the battery, one or morecells, and/or the rotor. In example embodiments, the microprocessor 606may also receive signals from the voltage detector circuit 618 and maydirect the switching network 607 accordingly. According to exampleembodiments, the switching network 607 may connect the battery or cells604 with the rotor 602 for charging when a voltage across the rotor 602has reached or exceeded a predetermined value, or when a certainrotational speed has been reached. According to an example embodiment,power may be supplied externally by the homopolar generator charger 600via output brushes 610 by connecting one or more of the rotor 602,battery or cells 604 to the output. According to an example embodiment,the rotor 602 may be switched out of circuit and the battery or cells604 may be connected to the output for supplying power to externaldevices via the output brushes 610. According to example embodiments,two or more cells may be connected in series via the switching network607 to provide power output at an increased voltage.

An example method 700 for converting rotational kinetic energy toelectrical energy for charging one or more battery cells will now beexplained with reference to FIG. 7. In block 702, and according to anexample embodiment, the method 700 includes rotating, by a shaft, arotor in a magnetic flux field to generate current, wherein the rotorcomprises an electrically conductive portion having an inner diameterconductive connection surface and an outer diameter conductiveconnection surface, and wherein a voltage potential is induced betweenthe inner and outer diameter connection surfaces upon rotation in themagnetic flux field. In block 704, the method 700 includes selectivelycoupling the generated current from the rotating rotor to terminals ofthe one or more battery cells, wherein the terminals comprise a positiveterminal and a negative terminal, and wherein the positive terminal anda negative terminal are electrically connected to respective inner andouter, or outer and inner diameter connection surfaces, wherein the atleast one battery cell is mounted substantially coaxially with respectto the shaft. The method 700 ends after block 704.

According to example embodiments, brushes may be utilized for makingelectrical connections of surfaces on the rotor, controller, and/orbattery. According to example embodiments, such surfaces may includeslip rings that may provide conductive surfaces for which the brushesmay make electrical contact with portions of the rotor, controller,and/or battery. In example embodiments, the brushes may include metalfibers, carbon compounds, or conductive liquids, such a liquid metal.

According to example embodiments, certain technical effects can beprovided, such as creating certain systems, methods, and apparatus thatprovide efficient utilization of energy conversion. Example embodimentsof the invention can provide the further technical effects of providingsystems, methods, and apparatus for providing high currents for chargingbattery cells.

In example embodiments of the invention, the homopolar generator charger200, 300, 500, 600 may include any number of hardware and/or softwareapplications that are executed to facilitate any of the operations.

In example embodiments, one or more I/O interfaces may facilitatecommunication between the homopolar generator charger 200, 300, 500,600, and one or more input/output devices. The one or more I/Ointerfaces may be utilized to receive or collect data and/or userinstructions from a wide variety of input devices. Received data may beprocessed by one or more computer processors as desired in variousembodiments of the invention and/or stored in one or more memorydevices.

One or more network interfaces may facilitate connection of thehomopolar generator charger inputs 200, 300, 500, 600 and outputs to oneor more suitable networks and/or connections; for example, theconnections that facilitate communication with any number of sensorsassociated with the system. The one or more network interfaces mayfurther facilitate connection to one or more suitable networks; forexample, a local area network, a wide area network, the Internet, acellular network, a radio frequency network, a Bluetooth™ (Owned byTelefonaktiebolaget LM Ericsson) enabled network, a Wi-Fi™ (owned byWi-Fi Alliance) enabled network, a satellite-based network any wirednetwork, any wireless network, etc., for communication with externaldevices and/or systems.

As desired, embodiments of the invention may include the homopolargenerator charger 200, 300, 500, 600, with more or less of thecomponents illustrated in FIGS. 1-6.

According to additional example embodiments, the rotor may include acomposite conductive structure. For example, the rotor may be made withmaterials including, but not limited to fiberglass, sintered metals,alloys, graphite composites, etc. According to example embodiments, therotor conductive surface or disk may be evaporated or deposited onto abase material. According to example embodiments, the rotor may include acopper outer casing. According to example embodiments, the homopolargenerator charger may include an outer casing that may be made ofvarious non-conducting materials with the required structuralproperties. In example embodiments the homopolar generator may includeelectrodes or electrical connection regions or surfaces that are madefrom of nickel oxyhydroxide and/or a hydrogen absorbing alloy. Accordingto example embodiments, two or more rotors can be stacked to providedifferent configurations, redundancy, and/or increased power outputcapacity.

According to example embodiments, the homopolar generator charger mayprovide pulsed current output. For example, a connecting circuit may becompleted and opened in succession to provide a current path between therotor inner and outer conductive regions and other components. In anexample embodiment, during the period when the connecting circuit isopen, a charge differential may build on the rotor until a balance ofcharge is met. Closing the circuit may allow the electrons to flow,similar to a capacitor, until charge is depleted.

According to example embodiments, frictional losses due to rotation ofthe rotor, battery, and other associated rotating components may bereduced by dimpling any surface where there is no brush or contact. Thisincludes unused areas of the shaft and areas that have clearance for airto pass between, and can be applied to the facing surfaces of the magnetarray and magnets themselves. According to example embodiments, drag maybe reduced via the dimpling by creating a boundary layer of turbulentair at exposed surfaces. In an example embodiment, dimpling may also beutilized to enhance heat dissipation.

According to an example embodiment, the homopolar generator charger'srotor may comprise a solid copper disk and a battery as previouslydescribed. Experiments have shown that an 18 inch by ¼ inch solid copperrotor is capable of sustaining 1500 amps in a field of 13000 gauss. Inan example embodiment, copper may be applied to the outer surfaces ofthe rotor via electroplating. In an example embodiment, the rotor may bemade from a solid copper disk or from an alloy. In an exampleembodiment, a solid shaft made from a similar alloy, and configured topass through the disk center, may facilitate the conduction ofelectricity and maintain the structural integrity of the unit.

In example embodiments, the rotor and shaft can be supported by variousmeans. According to an example embodiment, a housing or structure maysupport the rotor assembly in position and may to allow the rotor torotate on a common axis. According to an example embodiment, ends of therotor may be supported on roller bearings. In an example embodiment,pressurized gas, oil, or magnetic suspension may be utilized to reducemechanical resistance. According to example embodiments, ceramics andother non-conducting components may be utilized to eliminate currentflow in unwanted areas.

In accordance with example embodiments, current may be supplied toexternal component, or between components associated with the homopolargenerator via brushes. In example embodiments, solid copper, graphite,sintered, liquid metal, or other brushes may be mounted in standardbrass holders on each side of the rotor's shaft and on the periphery ofthe rotor conductor or disk.

According to example embodiments, the generated current and/or voltageoutput from the homopolar generator rotor may be dependent on themagnitude of the magnetic field, the square of the conductor's radiusimmersed in the magnetic field of a given magnitude, and the angularvelocity of the conductive portion of the rotor. Other factors affectingoutput include composition and size of the conductor or rotor,mechanical resistance, magnetic coupling with exterior objects, brushmaterials, etc. Eddy currents allowed to flow in a portion of the diskor conductor outside the field can reduce the efficiency.

According to another example embodiment, portions of the rotor mayinclude embedded wound coils, each connected in a manner to produce avoltage and current output. According to an example embodiment, astator, comprising multiple stationary magnets arranged in alternatingnorth-south-north-south ring configuration, may be mounted around thecenter of a larger magnet. In an example embodiment, a drive motor maybe integrated with the rotor. In an example embodiment, a wire-woundgenerator may be utilized as a motor. In accordance with exampleembodiments, regenerative systems, which may include a generator/motormay be used in conjunction with the homopolar generator charger.

According to this example embodiment, an inner generator/motor may beutilized in conjunction with the rotor of the homopolar generator. Forexample, an inner generator/motor may comprise a hub-type of wire-woundmotor. In accordance with an example embodiment, when the rotor isdecelerating or coasting, the rotor may act as a flywheel. In an exampleembodiment, kinetic energy from the rotor assembly may providemechanical leverage when the motor is switched to generating mode, suchas in a regenerative system. Accordingly, the rotor in the regenerativemode may have certain mechanical advantage due to its proximity to thecenter of the shaft. However it may have the classic back torque or backelectromotive force associated with standard generators. The back torqueor back electromotive force may be minimal if designed for low voltageof 3 volts or less.

According to example embodiments, outer (non-rotating) magnetssurrounding the inner (rotating) magnets may be utilized for producingthe high currents that are typically associated with a homopolargenerator with a solid conductor disc rotor. According to exampleembodiments, rectification may be utilized for the inner magnet portion,and the outer portion associated with the stationary part may producedirect current.

Example embodiments may utilize a circumferentially segmented rotor madeof at least two conductors isolated from each other at theirperipheries. Other example embodiments may include a rotor having aconductor shaped in the form of a spiral.

In accordance with an example embodiment, the homopolar generatorcharger may include a composite copper disk mounted inside amagnetically closed metal housing. In an example embodiment, magnets maybe attached to the inside of the housing. For example, the housing mayinclude two half pieces, having parabolic-shape, or other suitableshape. In example embodiments, bearings may be mounted in the center ofeach half, allowing the magnetic flux from ends of the single or stackedmagnets to couple back through the housing. This arrangement may reduceexternal fields and magnetic coupling of exterior ferrous objects.According to an example embodiment, the housing may be made of soft orcast iron. Example embodiments of the housings may be heat treated forfixing dipole alignment (or randomization) of the material. According toan example embodiment, nickel may be included in the housing material toreduce hysteresis. In other example embodiments, laminated structuresmay be employed reduce induced eddy currents. In an example embodiment,a brush system (solid or liquid) may be mounted and isolatedelectrically at the center between the halves of the housing structure.In an example embodiment, outer diameter surface of the brush assemblymay be constructed from the same materials as the housing halves toallow the magnetic flux a point of return.

According to an example embodiment, the rotor may include integratedrings of individual rechargeable batteries or cells separated byinsulators. In one example embodiment, the innermost battery or cell maybe placed in a ring adjacent to the shaft. In an example embodiment, theinnermost battery or cell may be surrounded radially by a second batteryor cell, and so-forth to a desired diameter. According to an exampleembodiment, as the circumference is increased, the radial thickness ofeach cell or battery may be modified to keep each battery or cell ringat approximately the same internal resistance.

According to another example embodiment, a straight shaft design may beutilized in high speed applications ranging from approximately 10,000 toapproximately 100,000 revolutions per minute. In this embodiment, ashaft may be made of neodymium-iron-boron being solid in constructionbut with appropriate thickness to carry high currents withoutoverheating. Any number of raised surfaces can be machined into theouter surface of the rotor shaft. According to example embodiment, theraised machined surfaces may be located over the center of any opposingmagnetic fields. In an example embodiment, the surface of the shaft maybe electroplated with conductive metal to reduce oxidation and providepoints of brush contact for current output. According to an exampleembodiment, the shaft may be capped with bearing supports of magneticmaterial or ferrous ends for oil, air, and gas or magnetically floated.In accordance with an example embodiment, the shaft, when rotated athigh speed, may maintain a negative polarity on the shaft center withcharge separation occurring at or near the surface of the shaft.Accordingly, charge separation may occur at the point of the centerlinewhere the magnetic flux is closest to zero. According to exampleembodiment, brush slots may be filled with a liquid metal and cappedunder slight pressure, and lugs may be milled into these areas forcurrent extraction. In accordance with an example embodiment, the outerhousing may be made from cast iron to close the unused poles and forcethe internal magnetic flux lines compress and concentrate in the areawhere outer raised areas of the shaft may intersect the compressedfields at 90 degrees. In an example embodiment, this type of generatorcan be used in high temperature applications, such as in turbine exhaustsystems, and may recover energy form systems that have exhaust as abyproduct of operation. Any enclosed tube in which a liquid, gas, orvapor flows from a high potential to a lower potential is a candidatefor this type of generator.

According to an example embodiment, a rotor assembly made of printedcircuit material may be utilized to provide a voltage potential orcurrent source. In an example embodiment, the printed circuit rotor maybe mounted to shaft. In an example embodiment, the printed circuit rotormay be mounted adjacent to another rotor. Example embodiments mayinclude a multilayer printed circuit rotor. Example embodiments mayinclude an integrated switching controller with or adjacent to theprinted circuit rotor. The printed circuit rotor may provide alightweight design and may allow for complex conductive patterns on therotor.

Example embodiments may include a conducting disk composed of aconductor or materials that conduct electricity and mounted on a shaftor axle so that it can be rotated within the fields of one or morepermanent magnets. According to example embodiments, the magnets have asufficient diameter to produce a field that is larger than the diameterof the disk or rotor. In an example embodiment, the disk may include acomposite copper rotor or other conductor in which current and voltageis known to flow when rotated in a magnetic field. The rotor may includean inner and outer diameter conducting rings or surfaces, as describepreviously. The area between the inner and outer diameter conductingrings or surfaces may include layers of capacitor components in a radialorientation. In one example embodiment, the negative terminal of thecapacitor component may be connected at the center, and positiveterminal may be configured for electrical connection at the outerradius. According to example embodiments, the capacitor may include twoconductors separated by a dielectric or non-conductive region orinsulator. The conductors thus hold equal and opposite charges on theirinner and outer surfaces, and the dielectric develops an electric field.According to example embodiments, the capacitor parts may be arranged ina cylindrical form.

According to example embodiment, rotor systems in a cylindrical shapemay have a shaft made from NdFeB material or is cast in the requiredshape. In example embodiments, beryllium or copper conductors can befitted to the NdFeB shaft to allow for current extraction directly fromthe ends.

Example embodiments, may include both the shaft and rotor combination toinclude both the north and south pole, with a conductor of copper orother material fit to the center of the magnetic rotor. Such anembodiment, may draw current through the magnet and shaft, being theconductor in combination. This example embodiment may result in aconfiguration similar to a standard rotor system, but it may includecomposite NdFeB for current conduction. Example embodiments may includeelectroplating the assembly with highly conductive materials prior tomagnetization to both protect the NdFeB from the elements and provide aconductive path for the flow of current, all in one assembly. Theassembly may then be magnetized through its thickness one side beingnorth and the other being south. The conducting ring being mounted inits centerline may provide the highest concentration of field strengths,as the highest fields are on the surface and interiors of the magnets.In an example embodiment, the rotor section is magnetized. In thisconfiguration, the north side may rotate in the same direction as thesouth.

In accordance with example embodiments, the rotor system may be mountedon or in many enclosure configurations, and may have either a closedmagnetic flux circuit or open magnetic circuit. According to one exampleembodiment, a rotor may be supported by non-magnetic pedestals, but mayutilize permanent- or electro-magnets. In one example, magnets may beapproximately six inches in diameter, one half inch thick, and mayinclude a one and three-eighths inch hole in the center for the shaft topass through. In an example embodiment, six magnets may be used.According to an example embodiment, the first magnets on each side of adivided housing may be bolted to the housing. The next two magnets maybe magnetically coupled north to south or vice versa, three on eachside. This arrangement may be utilized to increase and guide themagnetic field. In an example embodiment, two halves of a housing may beassembled in a way that may subsequently receive additional components,including the rotor, shaft, rechargeable battery, switching controller,etc.

In accordance with example embodiments presented herein, it should beunderstood that the housings and materials mentioned are not onlysubject to electromagnetic or permanent magnet fields, but also fieldsthat are created by the flow of current within the system. All of thefactors that govern permanent sources of fields may also apply to fieldscreated by current flow. In example embodiments, shielding may beutilized to prevent or guide certain forces. For example, somematerials, such as non-ferrous brushes and copper conductors, may becomeattracted to each other through the magnetic force created by currentflow, and may need to be shielded to prevent unwanted forces.

In accordance with example embodiments, the rotating portion of thehomopolar generator charger may include a stack of disk shaped rotorsbetween stationary or affixed magnets, so that the magnets rotate withthe shaft. In this example configuration, the rotor disk, batter disk,magnet disk(s), and any switching control circuitry may be mounted on acommon shaft.

Example embodiments may include many options for the type ofrechargeable battery or cell to be used in a system, and may bedependent on many factors, such as use or type of application,environment or generator configuration, battery resistance, chargeabsorption over time, temperature, and issues such as electrolyteseparation due to centrifugal forces.

Nickel metal hydride (NmH) batteries may be utilized as rechargeablebatteries, according to an example embodiment. Such batteries may have alow internal resistance, and may have high durability. Lithium-basedcells (for example, lithium-ion, lithium-polymer, etc.) may be utilizedas rechargeable batteries, according to another example embodiment.According to one example embodiment, a dual battery bank system may beused, for example, to provide power from one bank while another bank ischarging. According to example embodiment, a switching system, such asthe ones previously describe, may be used for selective routing ofinternal conductors.

According to an example embodiment, an internal or external bank ofbatteries may be charged at low voltage and high current using thehomopolar generator charger. According to this example embodiment,batteries may be charged as individual cells in parallel. According toan example embodiment, the bank can include individual cells. Forexample, NiM cells may have nominal associated voltages of approximately1.2 to 1.5 volt. Li cells may have nominal associated voltages in therange of approximately 2.8 to 3.3 volts. Bank size or number of cellsmay be determined by the amount of energy needed by the load for a giventime. A generator size may also be determined based on the size of thebattery bank. For example, 180 1.2 volt batteries may requireapproximately 300 amps to recover from a 90% discharge. An examplegenerator capable of providing the 300 amps and at a voltage of 1.5volts, according to embodiments, could conceivably recharge the bank in15 minutes. If the depth of discharge is less, then the time required toreach 100% charge may be reduced. For comparison purposes, a bank ofthis size can take from 2 to 20 hours to recharge by conventional means,particularly if the batteries are charged in series.

According to example embodiments, after reaching full (or near fullcharge), the battery bank may be switched to a series configuration toprovide an increased voltage output for powering devices. In an examplewhen a discharge limit is reached, the bank may be switched back toparallel and current may be directed to charge the bank.

According to an example embodiment, and as previously discussed, abattery or cell bank may be rotated with the rotor. In an exampleembodiment, a disk shaped battery may include a center hole being eithera positive or negative pole. In an example embodiment, the battery maybe approximately 8 inches in diameter, approximately 5/16 of an inchthick with approximately a 1 inch diameter hole in the center for theshaft to pass through, or for attachment to the shaft. In an exampleembodiment, the outer shell of the battery may be copper or copper cladto form the rotor. According to an example embodiment, the negativeterminal of the battery may include an electrode composed of a hydrogenabsorbing alloy. The electrode may be in a grid or it may be perforatedto increase its surface area. According to example embodiments, thepositive electrode can include nickel oxyhydroxide. According to anexample embodiment, a disk battery of this size would weighapproximately 2.5 pounds. Each battery may be capable of 800 to 1000watts per kilogram specific power.

According to example embodiments, one or more rotors may be mounted on acommon shaft. Each may be separated by a disk shaped magnet with thepoles on the faces north and south. Such an example configuration mayalso be connected in series to provide higher voltage potentials but atlower amperage capacity. The reverse is also true with lower potentialand higher amperage capacity.

According to example embodiments, the applications for the homopolargenerator charger system may include, but are not limited to wind energyharnessing, automotive electric vehicle industries, geothermal systems,hydropower, tidal and wave energy harnessing, uninterruptable powersupplies, emergency power, etc. For example, instead of large generatorsproducing high speed and high voltage potentials, the generator could bea low speed, high current design that could provide current in line withthe nature of high capacity cells. Advantages may include a reductionweight, operation under light loads or cruising speeds, and highefficiency.

While certain embodiments of the invention have been described inconnection with what is presently considered to be the most practicaland various embodiments, it is to be understood that the invention isnot to be limited to the disclosed embodiments, but on the contrary, isintended to cover various modifications and equivalent arrangementsincluded within the scope of the appended claims. Although specificterms are employed herein, they are used in a generic and descriptivesense only and not for purposes of limitation.

This written description uses examples to disclose certain embodimentsof the invention, including the best mode, and also to enable any personskilled in the art to practice certain embodiments of the invention,including making and using any devices or systems and performing anyincorporated methods. The patentable scope of certain embodiments of theinvention is defined in the claims, and may include other examples thatoccur to those skilled in the art. Such other examples are intended tobe within the scope of the claims if they have structural elements thatdo not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal language of the claims.

Further embodiments of the invention are directed to simultaneouscharging and discharging of battery banks. Such simultaneous chargingand discharging can be implemented by virtue of separation between powersource (e.g., homopolar generator) and load (e.g., appliances or otherdevices requiring power for operation), according to certain embodimentsherein. In one embodiment, such separation may be accomplished at leastin part by one or more battery banks that may be separated such thatportions of the battery bank may be charged in parallel while otherportions may be discharged in series. The portion of the battery bankthat is being charged in parallel may continue being charged whileanother portion of the battery bank may be selectively disconnected froma power source for discharge to an inverter (e.g., DC-to-AC inverter)for supplying power to a load, hence separation between source and load.Once the discharging battery has completely discharged, it may beselectively connected to and recharged for future power distribution,while the portion of the battery bank that was previously being chargedmay be selectively disconnected and used to supply power to the sameload, i.e., the load that was receiving its power source from the otherportion of the battery bank, or a different load. Thus, in the manner ofselectively switching between portions of battery banks that effectivelyisolate source and load, an extended or improved supply of power may beprovided by implementing systems and processes described herein.

Certain embodiments herein are directed to attaining maximum powertransfer from source to load when charging and discharging battery banksby matching impedances, i.e., the total opposition to alternatingcurrent by an electric circuit, between source and load. FIG. 8 depictsan example configuration of an apparatus for implementing such maximumpower transfer between source and load. A generator or source 802, e.g.,the homopolar generator described above, may supply power to a batterybank 804, which may have separate portions 804 a and 804 b. Each portionof the battery banks 804 a and 804 b may contain any number of batteriesor battery cells. As shown in FIG. 8, battery portion 804 a may receivea charge from source 802 while battery portion 804 b may simultaneouslydischarge power to load 806. A continuance impedance monitor, such asthat which may be provided by a switching controller 506 of FIG. 5 inone embodiment, may continually modify an impedance of the battery bank804 to match an impedance of the source 802. For example, the continuousimpedance monitor 808 may match the impedance of the battery portion 804a to that for the source 802 and simultaneously match the impedance ofthe battery portion 804 b to that for the load 806. Thus, by separatingsource from load, certain embodiments herein may simultaneously controlan impedance of the source and an impedance of the load independently ofone another, e.g., to match impedances.

Numerous technical effects may result from implementations of certainembodiments described herein. As an example, impedance matching mayenable battery banks to absorb energy faster and more efficiently whilealso discharging more efficiently. Additionally, impedance mismatchesbetween source and load may be reduced, and therefore, conversion lossesmay be reduced. In certain embodiments, the battery bank may be theload, and thus control over a battery's impedance may be accomplished inthese embodiments. Further, resistances of battery banks in series maybe eliminated or greatly reduced by virtue of impedance matching asdescribed herein.

While certain embodiments relate to simultaneous charging, discharging,and matching of impedances, some embodiments may involve such functionsbeing performed substantially simultaneously or at approximately thesame time other functions are performed. Functions or processesaccording to these embodiments may experience a lag or delay but maygenerally be performed while other described functions or processes areoccurring.

According to various embodiments, a battery bank may be included indifferent locations with respect to a rotor of a homopolar generatorcharger. In one embodiment, a battery bank may be included within arotor, i.e., integral to the rotor, while a battery bank may be externalto the rotor in another embodiment. According to a configuration inwhich a battery bank is integral to a rotor, an output connection mayexist to connect the battery bank to at least one additional batterybank. In one example, a source may charge the integral battery bank and,upon doing so, the source may then charge the external battery bank.Such charging of the external battery bank may be by virtue of thesource completing its charge of the integral battery bank or a result ofthe source being switched, e.g., via a switching controller, to supply acharge to the external battery bank. According to this configuration, asmaller battery bank that may be internal to a rotor may act to powersupply to a larger, external battery bank, which may in turn supplypower to a load.

Other embodiments are directed to modifying the magnetic fieldrelationship between the magnets and one or more rotors. In oneembodiment, an alternating current (AC) signal may be used to impart asonic frequency to the magnets, which may in turn expose a spinningrotor or conductor to more lines of force. Such exposure may have theeffect of inducing additional current. In one embodiment, the AC signalmay be produced by multiple rotors, e.g., a primary rotor and asecondary rotor, operating together in the homopolar generator system.An inductive material, such as steel or iron, may be laminated to thesecondary rotor and may connect to an input associated with a continuousimpedance monitor 808 such that when the secondary rotor rotates, alow-voltage AC signal (instead of a chopped DC signal) may be producedand fed into the continuous impedance monitor for use in modifyingimpedances in batteries or performing other functions. In oneembodiment, the AC signal may be used to determine, e.g., by thecontinuous impedance monitor 808, an amount by which to modify theimpedance of batteries being charged. The continuous impedance monitor808 may continuously monitor such voltage, in one embodiment. Asdescribed above, by modifying DC source energy provided for a batterywith an AC signal from a rotor source, e.g., a secondary rotating rotor,in contact with an inductive material, a battery may respond morerapidly as the AC signal more directly affects the ionic exchange (boththe chemical and kinetic processes), thereby making it easier to absorbcharge at a faster rate. The technical effect of such a configurationmay be reduced time required to charge one or more batteries.

Other embodiments may be directed to increasing efficiency of ahomopolar generator in part via the use of piezoelectric materials. Inone embodiment, a rotor may include a copper disk and a differentconductive material, and may serve as a battery (when stationary) or acapacitor (when moving). As alloys which may be used for a rotor vary,the impedance may also vary. In certain embodiments, impedance may bemodified according to the material used such that as different types ofalloys or materials are used, the AC signal received by the continuousimpedance monitor may also change to account for the change in alloys orother materials.

Certain embodiments herein relate to providing an amount of charge tobatteries that is consistent with the amount of charge required by abattery, not the amount of charge that a battery may desire or becapable of receiving over a certain time period. By updating a source orgenerator with information that a battery bank's impedance is a certainvalue, the generator may adjust accordingly such that the impedance ofthe battery bank is matched to provide improved power output to thebattery bank. In this way, the generator is a variable impedancegenerator and is able to provide such functionality by virtue of alow-impedance source or generator.

Certain embodiments herein may also relate to a generation and storagesystem, i.e., power may be both generated and stored via use of such ageneration and storage system or unit. Losses that may result from powergeneration and storage systems described herein may be compensated forvia renewable energy sources, such as solar panels, wind, or small watergenerators.

Various conductor materials may be included on the surface of therotors, e.g., via lamination or other attachment mechanisms that maylayer such materials on a rotor, in one embodiment. The amount ofcurrent provided from a rotor may vary according to the type ofmaterial. Such materials may include piezoelectric materials,nanomaterials, copper materials, or alloys, as non-limiting examples.Piezoelectric materials may be used in association with thepiezoelectric effect, which may be referred to as the linearelectromechanical interaction between the mechanical and the electricalstate in crystalline materials with no inversion symmetry. Materialsthat may exhibit either a direct or reverse piezoelectric effect mayexist in certain embodiments herein.

In one embodiment, a steel material may be laminated to one or morerotors. According to this embodiment, the inductance and resistance ofthe steel material may be higher than that in other materials. Suchhigher inductances and resistances may be desirable in embodiments whena relatively higher voltage and relatively lower current may bedesirable. Additionally, the magnets described herein may include atransducer to facilitate energy conversion in association with certainembodiments described herein.

Other embodiments are directed to computer modeling to determine andillustrate the performance of generators and batteries graphically. Suchcomputer modeling may be used to model the flow of current and its useby one or more switching controllers to manage simultaneous batterycharging and discharging as described herein. FIG. 9 illustrates anexample such computer simulation depicting one embodiment of theinvention.

Example configurations of the homopolar generator are further describedin FIGS. 10-13. The example configurations may include variations of theshaft, rotor, magnet arrangements, connection systems or brush systems,housings for enclosing these and other components, and other componentsof the homopolar generator.

As an example, the homopolar generator may include a housing that mayenclose various components of the homopolar generator. Such a housingmay include two halves in the example embodiment shown in FIG. 10. Theexample housing may include a top half 1001 a and a bottom half 1001 bas shown. Both halves 1001 a and 1001 b are shown in an exploded viewfor purposes of visibility and explanation of the components within thehousing. Reference to the housing as including two halves is forpurposes of illustration and is not meant to limit the example housingto include two portions each of which are approximately 50% in length,width, depth, or other dimension. While such a configuration may existin one example, numerous other examples may exist.

According to one example configuration, at least a portion of thecomponents shown in the top half 1001 a of the housing may also exist inthe bottom half 1001 b of the housing. In this way, the two halves orportions 1001 a and 1001 b may mirror or partially mirror one another inexample embodiments. Therefore, while FIG. 10 illustrates componentsprimarily in the top half 1001 a, at least a portion of these componentsmay exist in the bottom half 1001 b, as will be described in otherexample embodiments below.

As shown in FIG. 10, the example homopolar generator may include ahousing that includes a mounting surface 1004 for supporting a trackhousing 1010 and two platens 1002 a and 1002 b on opposite sides of thetrack housing 1010. As will be described in greater detail below, softiron plates or other types of materials may be coupled to at least aportion of the platens 1002 a and 1002 b, and the mounting surface 1004to form a housing or enclosure for enclosing other components of thehomopolar generator 1000 as described herein. In one configuration, themounting surface 1004 may be located in the center between the platens1002 a and 1002 b to facilitate the implementations and processesdescribed herein. Various types of materials for the platens 1002 a and1002 b, and the mounting surface 1004 and may be used including, but notlimited to, metal, steel, copper, other relatively high conductivitymaterials, silver, gold, aluminum, nickel, etc.

While the halves 1001 a and 1001 b are shown in an exploded view forpurposes of illustration, an actual example implementation of thehomopolar generator 1000 may include a top half 1001 a and a bottom half1001 b that are closer in distance to one another such that, among otherthings, the magnet array 1004 may be proximate to surfaces of the rotor1014. As mentioned, soft iron plates or other materials may be coupled(e.g., bolted) along the perimeters of the platens 1002 a and 1002 b toform a complete or a partial enclosure. Such a configuration mayeffectively couple the outer and inner fields associated with thehomopolar generator 1000 and may in effect provide a relatively greatermagnetic field strength in the interior of the housing while eliminatingunwanted or stray fields exterior to the housing. In an exampleimplementation, the amount of flux density in the interior of thehousing may be approximately 1.3 Tesla, whereas the amount of fluxdensity associated with a housing that is not enclosed as described maybe approximately 0.8 Tesla. Thus, an approximate 60% increase may beobtained by virtue of configuring a housing as described above.

The above configuration of the housing (for example, the combination ofthe top half 1001 a and the bottom half 1001 b) is for purposes ofillustration and is not meant to be limiting. For example, the generallyrectangular shape of the housing may include various other shapes andconfiguration in other embodiments. The housing may have a parabolicshape or other suitable shapes in other example embodiments.

The track housing 1010 may include various components to facilitate theimplementations and processes described herein. For example, the trackhousing 1010 may include an upper track portion 1010 a and a lower trackportion 1010 b. An opening or groove along a central portion of thetrack housing 1010 may exist where the upper track portion 1010 a andthe lower track portion 1010 b join. Such a groove may receive at leasta portion of the rotor 1014, for example, the periphery of the rotor1014. The outermost edge of the rotor 1014 may be located at a distancealong a central axis of the track housing 1012, in one configuration.Various materials for the track housing 1010 may be used including, butnot limited to, plastic, hard plastic, wood, non-conductive materials,etc.

The track housing 1010 may house or enclose various components, such asa brush system 1040 that may include one or more brushes 1042, andvarious magnets having certain pole orientations embedded in the trackhousing 1010, among other components. In certain embodiments, the uppertrack portion 1010 a and the lower track portion 1010 b may include thesame or at least a portion of the same components. Each of thesecomponents and example configurations of the track housing 1010 will bedescribed in greater detail below.

FIG. 10 also depicts example shafts. For example, one or more cups 1016may act as a shaft for providing a linkage for rotation of the rotor1014. An opening in the rotor 1014 may enable the one or more cups 1016to pass through the rotor 1014, as shown, and provide such a linkage forrotation. According to an example configuration, the cups 1016 mayinclude two cups (e.g., an upper cup portion 1016 a and a lower cupportion 1016 b, which may be separated by the rotor 1014) may bothcomprise the shaft. As an example, FIG. 13 illustrates both an upper cupportion 1320 a and a lower cup portion 1320 b and will be described ingreater detail below. According to these configurations, at least aportion of the upper cup portion 1016 a may be coupled to a top surfaceof the rotor 1014, while at least a portion of the lower cup portion1016 b may be coupled to a bottom surface of the rotor 1014, as shown.According to this example configuration, the upper cup portion 1016 aand the lower cup portion 1016 b may serve as bushing surfaces that mayenable rotation of the rotor 1014 without the use of metallic bearingsand may further reduce typical losses at the point where the rotor 1014interfaces with the ball screw shaft 1020.

The ball screw shaft 1020 may pass through the cups 1016, for example,along a central axis of the cups 1016 as shown in FIG. 10. In oneconfiguration, a bushing may be coupled to an inner surface of one ormore of the cups 1016 and to the ball screw shaft 1020. For example, aperiphery of the bushing may be coupled to an inner surface of the uppercup portion 1016 a and/or the lower cup portion 1016 b, and an innerdiameter of the bushing may be coupled to ball screw shaft 1020. In someconfigurations, multiple bushings may be used to facilitate suchcoupling. The couplings provided by the bushings may reduce movement ofthe rotor 1014, including horizontal, vertical, or other directions, forexample, while the rotor 1014 is rotating. Various types of bushings maybe used, such as Teflon, steel, metal, etc. in some embodiments, abushing may be located on the outer surface of the cups 1106, forexample, on either or both of the upper cup portion 1016 a or the lowercup portion 1016 b. Such a location of the bushing may facilitate thesame or at least similar restriction on movement of the rotor 1014 asdescribed above.

In addition to passing through the center of the cups 1016, the ballscrew shaft 1020 may also pass through the platens 1020 a and 1020 b to,for example, facilitate securing the platens 1020 a and 1020 b in theirrespective positions relative to the rotor 1014. The ball screw shaft1020, along with other components, may secure the platens 1020 a and1020 b in their respective positions relative to the rotor 1014. A ballscrew nut 1022 may secure the ball screw shaft 1020 to the platen 1020a, and a separate ball screw nut (not shown) may secure the ball screwshaft 1020 to the platen 1020 b, in one configuration. In oneembodiment, the ball screw nut 1022 may be threaded into the platens1002 a and 1002 b such that various clearances of components in thehomopolar generator 1000 may be established with respect to the rotor1014. One or more shafts 1007 (four shown in FIG. 10) may further securethe platens with respect to the rotor 1014. In one configuration, theshafts 1007 may be sliding shafts with bushings 1008 that may facilitatesuch securement, as well as slidable movement of the shafts 1007.

As further shown in FIG. 10, a magnet array 1006 may be coupled to theplatens 1002 a (e.g., via epoxy, glue, tape, other adhesive, welds,etc.). The magnet array 1006 may include one or more magnets forgenerating a magnetic flux field in which the rotor 1014 may rotate. Themagnets in the magnet array 1006 may be opposed by magnets in anothermagnet array (not shown), which may be coupled to the platens 1002 b andmay also produce a magnetic flux field in which the rotor 1014 mayrotate. FIG. 12 illustrates an example of such opposing magnet arraysand will be described in greater detail below.

In one configuration, the magnet arrays may be located proximate to therotor 1014 and may be secured in such a position by virtue of theconfigurations described above. For example, the configurations andarrangements of the platens 1002 a and 1002 b, the ball screw nut 1022,and the shafts 2007 and coupled bushings 1008 with respect to oneanother, among other components, may enable such securement. In oneembodiment, the magnet arrays may be secured in a position that isproximate and parallel, or substantially parallel, to surfaces of therotor 1014. The coupling of the magnet arrays (for example, magnet array1006 and an opposing magnet array (not shown)) to the platens 1002 a and1002 b, respectively, may provide a method of coupling outer fieldsassociated with the homopolar generator 1000, as described above. Softiron plates, or other materials, may be coupled to the platens 1002 aand 1002 b to, in effect, complete a magnetic circuit including theouter fields or poles in which the platens 1002 a and 1002 b may act asmagnets in the homopolar generator 1000. Such a configuration, asdescribed above, may facilitate generating a relatively high amount offlux density in the interior of the housing that includes the top half1001 a and bottom half 1001 b.

A technical effect of the above configurations may include, among otherthings, relatively accurate and stable clearances of the magnet arrayswith respect to the rotor 1014, for example, while the rotor 1014 isrotating.

The above configurations, orientations, examples, etc., in FIG. 10 arefor purposes of illustration and are not meant to be limiting. Asdescribed, components in addition to, or other than, those shown in FIG.10 may also exist. For example, the rotor 1014 may include a bottom oropposing surface on the underside of the top surface shown in FIG. 10.The bottom surface of the rotor 1014 may also receive magnetic forcegenerated at least in part by an opposing magnet array.

An example configuration that includes such an opposing magnet array isshown in FIG. 12, in which the magnet array 1211 may include magnetsthat oppose magnets in the magnet array 1206. The magnet arrays 1206 and1212, which may be coupled to the platens 1202 a and 1202 b,respectively, as well as the magnet array 1006 in FIG. 10, may includemagnet compartments 1212 for receiving the magnets. Various sizes andshapes of the compartments may exist for receiving various sizes andshapes of magnets. Numerous other configurations of the magnet arraysand other components in the homopolar generator 1000 may exist in otherembodiments. Also as shown in FIG. 12, the homopolar generator 1200 mayinclude a track housing 1210 that may be coupled to a center surface1204 and supported at least in part by shafts 1207 that may includebushings 1208. The homopolar generator 1200 may further include a brushsystem 1220, which is comparable to a brush system that will bedescribed in greater detail below.

FIG. 11 illustrates a cross-section of a track housing, such as thetrack housing 1010 in FIG. 10 described above, and associatedcomponents. The track housing 1010 may include various components, suchas an upper track portion 1112 a, a lower track portion 1112 b, brushcompartments 1113 a and 1113 b recessed within the upper track portion1112 a and the lower track portion 1112 b, a rotor 1114, a linear arcring 1120, and multiple magnets 1116 embedded in the rotor 1114, amongother components.

In one configuration, the linear arc ring 1120 may be located around allor at least a portion of the periphery of the rotor 1114. In oneembodiment, the linear arc ring 1120 may be secured or coupled to therotor 1114 via various materials, such as epoxy, glue, tape, otheradhesives, welds, or other mechanisms for securing the linear arc ring1120 to the rotor 1114. The linear arc ring 1120 may include variousmaterials, such as metal, steel, copper, other relatively highconductivity materials, plastic, etc. In an example configuration, thelinear arc ring 1120 may be mounted to a base material, at least aportion of which may be coupled to the rotor 1114 for securing thelinear arc ring 1120 to the rotor 1114. Various other configurations mayexist for securing or coupling the linear arc ring 1120 to the rotor1114.

In one configuration, the linear arc magnets may be arrangedperpendicularly or approximately 90-degrees to the rotor 1114 instead ofbeing substantially parallel or along a periphery of the rotor 1114, inone embodiment. According to the substantially perpendicularconfiguration of the linear arc magnets, the control head of the motorcontroller may be located along an edge of (or proximate to) the lineararc magnets. Various other configurations may exist in otherembodiments.

According to certain configurations herein, the linear arc ring 1120 mayinclude one or more magnets (not shown), which may be referred to hereinas linear arc magnets. The linear arc magnets may be embedded in,adjacent to, or coupled to the linear arc ring 1120 such that the lineararc magnets may also be located along a periphery of the rotor 1114. Inone embodiment, the linear arc magnets may be secured to the linear arcring 1120 via various materials, such as epoxy, glue, tape, otheradhesives, welds, etc. Various types and materials of the linear arcmagnets may exist. In an example embodiment, the linear arc magnets mayinclude neodymium magnets and may be approximately ¼-inches inthickness. Numerous other types, thicknesses, other dimensions, etc., ofthe linear arc magnets may exist in other examples. In anotherconfiguration, the linear arc magnets may be embedded in the rotor.According to this configuration, the rotor 1114 may be a single,coplanar rotor material. In yet another configuration, the linear arcmagnets may be coupled to the rotor 1114. Various other configurationsmay exist.

The linear arc magnets coupled to the linear arc ring 1120 may bearranged in an alternating north-south north-south configuration, in oneembodiment. The linear arc magnets may serve as a drive motor or alinear arc motor that may turn the rotor 1114. In one embodiment, thelinear arc motor formed by the linear arc magnets may be driven by amultiphase (for example, a 3-phase) motor controller (not shown).According to one configuration, the motor controller may include acontrol head that includes a set of coils for driving the rotor 1114 orcausing the rotor 1114 to rotate. In one configuration, the control headmay be located along an edge of the rotor 1114 such that the rotor 1114may be driven along its periphery. In one embodiment, the control headmay be approximately 6-inches in length. Various other lengths and otherdimensions may exist in other configurations. In one embodiment, themotor controller may capture and provide data, in real-time or nearreal-time, associated with a speed of the rotor 1114, current associatedwith the rotor 1114, voltage input slip rate, ramp-up curve, and otherperformance data. In some embodiments, a drive motor other than a lineararc motor configuration as described above may be used. According tothese embodiments, any external motor that may be configured orotherwise capable of rotating the rotor 1114 may be used.

Also as shown in FIG. 11, the rotor 1114 may include multiple magnets1116 that may be embedded in the rotor 1114. The multiple magnets 1116may also be secured or coupled to the rotor 1114, in other embodiments.As shown, the multiple magnets 1116 may be located inside the linear arcring 1120, or put another way, at a distance closer to the center of therotor 1114 than the linear arc ring 1120. All or at least a portion ofthe magnets 1116 may face either north or south on one surface of therotor 1114. Thus, in one configuration, the magnets 1116 may eachinclude the same pole facing one direction. The magnets may be ¼-inchthick in one embodiment, or may be various other thicknesses, lengths,etc., in other embodiments.

In one configuration, the upper track portion 1112 a may includemultiple magnets (not shown) that may be recessed within or coupled tothe upper track portion 1112 a and may be located a distance above themultiple magnets 1116. As will be described, the lower track portion1112 b may also include magnets recessed therein or coupled thereto insimilar fashion to that described in association with the upper trackportion 1112 a. The magnets in the upper track portion 1112 a may opposethe magnets 1116 such that once the rotor spins (for example, via thelinear arc motor described above), the rotor 1114 may float in themagnetic flux generated at least in part by the magnets 1116 and theopposing magnets in the upper track portion 1112 a. Put another way,gyroscopic stabilization or spin stabilization may occur, therebyenabling the rotor 1114 to float.

In one embodiment, the opposing magnets in the upper track portion 1112a may be the same or approximately the same in number and size as themagnets 1116. The opposing magnets may also be embedded within the uppertrack portion 1112 a such that they are directly above, or substantiallyvertical to, the magnets 1116. The upper track portion 1112 a may alsoinclude one or more compartments 1113 a for receiving brushes, such asthe brushes 1042 in FIG. 10. Example brush configurations will bedescribed in greater detail below.

As mentioned, each of the components described in association with theupper track portion 1112 a may also exist in the lower track portion1112 b. For example, one or more magnets may be embedded in the uppertrack portion 1112 b and may oppose the magnets 1116 in the rotor 1114to further facilitate floating of the rotor 1114, as described above. Asanother example, the bottom half 1112 b may also include brushcompartments 1113 b for receiving brushes, such as the brushes 1042 inFIG. 10.

The example configuration in FIG. 11 is shown for purposes ofillustration and is not meant to be limiting. Numerous otherconfigurations may exist. For example, the illustrated number of themagnets 1116, spacing between each of the magnets 1116, spacing betweenthe magnets 1116 and the linear arc ring 1120, etc., may vary in otherconfigurations. Also, the upper track portion 1112 a may represent acutaway section of an actual upper track portion 1112 a for purposes ofexplanation. The magnets 1116, or at least a portion thereof, may be atleast partially covered by the track housing (e.g., the upper trackportion 1112 a and the lower track portion 1112 b).

Returning to FIG. 10, the track housing 1010 may include a brush system1040 that may include multiple brushes, such as the brushes 1042 and1044. A portion of the track housing 1010 has been cut away tofacilitate viewing the brush system 1040, which may be otherwiseenclosed within the track housing 1010 in certain embodiments herein. Asshown in FIG. 10, at least a portion of the brushes in the brush system1040 may be located in the upper track portion 1010 a (for example, thebrushes 1042) and at least a portion of the brushes in the brush system1040 may be located in the lower track portion 1010 b (for example, thebrushes 1044). Although only two brushes 1042 and two brushes 1044 areindicated via arrows in FIG. 10, each of the brushes coupled to theupper track portion 1010 a may be considered a brush 1042, while each ofthe brushes coupled to the lower track portion 1010 b may be considereda brush 1044.

In one configuration, the brushes 1042 and 1044 may be mounted to theirrespective track halves 1012 a or 1012 b. In one embodiment, suchmounting may be facilitated by the brush compartments 1113 a and 1113 bin FIG. 11. At least a portion of the brushes 1042 and 1044 may beinserted within the track portions 1010 a and 1010 b, for example, inthe brush compartments 1113 a and 1113 b, which may encircle and securethe brushes 1042 and 1044, respectively. In one configuration, at leasta portion of the brushes 1042 and 1044 may contact the a surface of therotor 1010. For example, the brushes 1042 may contact the top surface(or visible surface) of the rotor 1010, while the brushes 1044 maycontact the bottom surface of the rotor 1010. Such contacts of thebrushes 1042 and 1044 on the rotor 1014 may be located inside of themagnets 1116 shown in FIG. 11 such that the magnets 1116 are locatedbetween the linear arc magnets coupled to the linear arc ring 1120 andthe point at which the brushes 1042 and 1044 contact the rotor 1014.

In one embodiment, the brushes 1042 and 1044 may be mounted to theirrespective track portions 1010 a and 1010 b such that they alternatewith respect to one another. For example, as shown in FIG. 10, a brush1042 coupled to the upper track portion 1010 a may not be located in thesame opposing position as a brush 1044 coupled to the lower trackportion 1010 b. For purposes of explanation, if the track housing 1010includes positions 1, 2, 3, 4, and 5, then the brushes 1042 may belocated in positions 1 and 3, while the brushes 1044 may be located inpositions 2, 4, and 5 (or more generally, not positions 1 and 3 ornon-opposing positions). As another example, the brushes 1042 may belocated in positions 1, 2, and 5, while the brushes 1044 may be locatedin positions 3 and 4 (or more generally, not positions 1, 2, and 5 ornon-opposing positions). In this way, complete or approximate 100%coverage of the brushes 1042 and 1044 on the periphery of the rotor 1014may be provided. Such a configuration may have the technical effect ofreducing the formation of eddy currents, among other effects.

The brushes 1042 and 1044 may form a suspension system that mayfacilitate the brushes 1042 and 1044 remaining in contact with the rotor1014, for example, when the rotor 1014 is rotating. Such a configurationof the brushes 1042 and 1044 may maintain contact with the rotor 1014even with variations in the surfaces of the rotor 1014. Theconfiguration of the platens 1002 a and 1002 b, ball screw shaft 1020,ball screw nut 1022, bushings 1008, etc., may also facilitate thepresence of brushes that remain in contact (for example, constantcontact) with surfaces of the rotor 1014, in certain embodiments. Atleast a portion of the brushes 1042 and 1044 may be metal fiber, copper,steel, or other conductive materials, according to various embodimentsherein.

FIG. 13 depicts a cross-section of a homopolar generator 1300 that showsa shaft configuration including an upper cup portion 1320 a and a lowercup portion 1320 b (collectively referred to as cups 1320) coupled tothe rotor 1310 and a ball screw shaft 1330 passing through the cups1320. FIG. 13 also shows an upper track portion 1340 a and a lower trackportion 1340 b of a track housing that is coupled to a center surface1350, which may be located a distance above a platen 1302 and a distancebelow another platen (not shown).

According to one configuration, the central portion of the cups 1320 mayinclude brushes (not shown) extending toward the ball screw shaft 1330.In one embodiment, the cups 1320 may have a brush volume (for example,in terms of total number of inches of brush used) that is the same orapproximately the same as the brush volume used along the periphery ofthe rotor 1310, or the rotor 1114 as shown in FIG. 11. Such aconfiguration may provide a relatively balanced electrical circuit interms of the number of ohms in the circuit. A technical effect of such aconfiguration may include a reduction in eddy currents that may beformed between the brushes (for example, the brushes 1042 and 1044 inFIG. 10) and the surface of the rotor 1310 (or the rotor 1014 in FIG.10).

Certain configurations of the homopolar generator 1000 may include a busbar or similar opening, groove, recessed portion, etc., in the trackhousing 1010 for receiving and passing various components, conductivematerials, etc., for distributing electrical current, among otherthings. In some configurations, such a bus bar may not be located in thetrack housing but may be located within other portions, components, orsurfaces of the homopolar generator 1000. In some embodiments, at leasta portion of the bus bar may exist in one or more of the components orsurfaces of the homopolar generator 1000.

As mentioned, the above example configurations of the homopolargenerator may be used to charge various types of batteries. In oneembodiment, positive and negative electrodes may be coupled to terminalson such batteries and to brushes in the brush systems described above tofacilitate electrical communication from a rotor to a battery. Numerousother implementations, configurations, etc., may exist in otherexamples.

1. A method comprising: charging, by a battery system, a first portionof a battery comprising one or more first cells; determining that afirst impedance of the first portion of the battery is different than asecond impedance of a charging device electrically connected to thebattery; producing a first low-voltage AC signal to modify the firstimpedance to match the second impedance.
 2. The method of claim 1,further comprising: determining that a predetermined time threshold haselapsed; and determining that the first impedance is substantially thesame as the second impedance before the predetermined time threshold haselapsed.
 3. The method of claim 1, wherein a second portion of thebattery, comprising one or more second cells, is discharged while thefirst portion is being charged.
 4. The method of claim 3, wherein atleast a portion of the one or more first cells are charged in parallelwhile at least a portion of the one or more second cells are dischargedin series.
 5. The method of claim 3, further comprising: causing a thirdimpedance of the second portion of the battery to substantially matchthe second impedance.
 6. The method of claim 1, further comprising:determining a first signal; and causing a configuration of the firstportion of the battery to be modified from a series connection to aparallel connection.
 7. The method of claim 1, wherein causing the firstimpedance to match the second impedance comprises causing the firstimpedance to match the second impedance using a switching controller. 8.The method of claim 1, further comprising: determining an amount bywhich the first impedance differs from the second impedance using animpedance monitor.
 9. The method of claim 1, wherein the battery systemcomprises a variable impedance generator configured to modify the firstimpedance and the second impedance.
 10. The method of claim 3, whereinthe battery system is configured to simultaneously control a sourceimpedance corresponding to the first impedance and a load impedancecorresponding to a third impedance.
 11. A battery system comprising:memory comprising computer-executable instructions; and at least oneprocessor configured to access the at least one memory and execute thecomputer-executable instructions to: charge a first portion of a batterycomprising one or more first cells; determine that a first impedance ofthe first portion of the battery is different than a second impedance ofa charging device electrically connected to the battery; cause the firstimpedance to match the second impedance by producing a first low-voltageAC signal to modify the first impedance to match the second impedance.12. The battery system of claim 11, wherein the at least one processoris further configured to access the at least one memory and execute thecomputer-executable instructions to: determine that a predetermined timethreshold has elapsed; and determine that the first impedance issubstantially the same as the second impedance before the predeterminedtime threshold has elapsed
 13. The battery system of claim 11, wherein asecond portion of the battery comprising one or more second cells isdischarged while the first portion is being charged.
 14. The batterysystem of claim 13, wherein at least a portion of the one or more firstcells are charged in parallel while at least a portion of the one ormore second cells are discharged in series.
 15. The battery system ofclaim 13, wherein the at least one processor is further configured toaccess the at least one memory and execute the computer-executableinstructions to: cause the third impedance of the second portion of thebattery to substantially match the second impedance.
 16. The batterysystem of claim 11, wherein the at least one processor is furtherconfigured to access the at least one memory and execute thecomputer-executable instructions to: determine a first signal; and causea configuration of the first portion of the battery to be modified froma series connection to a parallel connection.
 17. The battery system ofclaim 11, wherein the at least one processor is configured to cause thefirst impedance to match the second impedance by executing thecomputer-accessible instructions to cause the first impedance to matchthe second impedance using a switching controller.
 18. The batterysystem of claim 11, wherein the at least one processor is furtherconfigured to access the at least one memory and execute thecomputer-executable instructions to: determine an amount by which thefirst impedance differs from the second impedance using an impedancemonitor.
 19. The battery system of claim 11, wherein the battery systemcomprises a variable impedance generator configured to modify the firstimpedance and the second impedance.
 20. The battery system of claim 13,wherein the battery system is configured to simultaneously control asource impedance corresponding to the first impedance and a loadimpedance corresponding to the third impedance.